Nutrient limiting factors

Plateau range - temperatures above 11°C. Where the mean temperature exceeds 11 °C, growth is accelerated and the limiting factors are light, moisture or nutrients. 

Nutrients—Nutrients, such as nitrogen and phosphorus and other trace elements, are necessary for cell growth because they are key biological building blocks.52,53 Addition of nutrients as a supplement helps ensure that concentrations of nutrients do not become a limiting factor for bioremediation. 

Armin Weiss (1981) presented some results of experimental work using mont-morillonite, he was able to show that the complete information present in a matrix is passed on to the daughter layers. In principle, the intercalating synthesis of a new layer of montmorillonite from the nutrient solution can be compared to the replication of a DNA chain. The distance between the layers is of great importance in these experiments and acts as a performance-limiting factor. 

Enhanced biorestoration is a means by which naturally occurring processes are deliberately manipulated to increase or enhance the rate of cleanup. Biological activity in the subsurface is controlled by the availability of one or more of the necessary metabolic requirements such as an electron acceptor or nutrient. Although electron acceptors are most often the limiting factor, inadequate availability of nitrogen, phosphorus, or micronutrients (such as potassium, copper, or even vitamins) can restrict optimum restoration. When the proper balance of these factors is established, the rate of chemical degradation is maximized. 

Certainly the possibility needs to be explored that nutritional supplements [and these may include not only substances known to be necessary for normal nutrition, but others as well (p. 184)] will prevent or cure the various types of mental disease. One cannot hope that a single nutrient factor, such as a vitamin, is going to be the answer for a multitude of people, even if their outward symptoms seem to be about the same. As each new vitamin or vitamin-like substance is discovered (and there are probably more to come), there is a great enthusiasm for its possibilities, oftentimes without regard for the fact that it is only one link in a chain and unless all links are present there is no chain. A single vitamin is likely to be a limiting factor in some process and not the only limiting factor. 

Rate-limiting factors for bioremediation can include a lack of sufficient organisms with the metabolic pathways required for degradation. Temperature, oxygen supply, contaminant availability, chemical structure of the contaminant, and soil chemistry can all effect aerobic biodegradation rates. Nutrients such as nitrogen and phosphorous are necessary for biodegradation. 

Slurry-phase bioremediation is not effective for treating metals and other inorganic contaminants. This limitation may be overcome by using slurry-phase bioremediation with a physical separation technology, such as soil washing or filtration. Temperature, pH, nutrient status, oxygen potential, and contaminant bioavailability can also be limiting factors in the slurry-phase bioremediation process. 

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